THE VARIABILITY OF BLOOD PRESSURE

Abstract

Studies such as those recently made by Alvarez,¹ and Diehl and Sutherland,² in which a surprisingly large number of presumably normal young adults are reported with elevation of blood pressure, lead one to wonder what proportion of these high readings can be attributed to normal fluctuations or variations of the blood pressure. Unquestionably many of the persons who show high pressures during required examinations of a group usually give normal readings; in fact, by taking repeated readings of the blood pressure of those university students who, on entrance examinations, had systolic pressures of 140 mm. or more, Diehl and Sutherland² found that the pressures of only 15 per cent of this group persisted at that high level. Other students showed high readings on some occasions and low readings on others, while the largest proportion were above "normal" on only the initial reading. In all groups, however, there were sufficient variations